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Full Discussion: Speeding up a Shell Script (find, grep and a for loop)
Top Forums UNIX for Dummies Questions & Answers Speeding up a Shell Script (find, grep and a for loop) Post 302222037 by era on Wednesday 6th of August 2008 01:00:26 AM
Old 08-06-2008
I don't understand the construction set | grep $value /tmp/date.out -- as far as I can tell, the output from set will not be used for anything.

Also, the conditional is a Useless Use of Test, and it will print to stdout any matches; I imagine that's undesirable. The following avoids those problems.

Code:
if ! grep "$value" /tmp/dave.out >/dev/null
then
  echo "$value"" >>/tmp/dave_files.out
fi

Still, if you had your list of PDF files in another file, one PDF per line, it could be as simple as

Code:
fgrep -vxf pdfs.txt /tmp/dave.out >/tmp/dave_files.out

The use of fgrep -x requires an exact match (not a regex match; you know that dot in a regex matches any character, for example) spanning the whole line (that's the -x). The -v causes only lines in /tmp/dave.out which are not anywhere in pdfs.txt to be printed.
 

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LEARN ABOUT DEBIAN

setmaillist

setmaillist(1)						      General Commands Manual						    setmaillist(1)

NAME

       setmaillist - create a binary mailing list

SYNOPSIS

       setmaillist bin tmp

DESCRIPTION

       setmaillist reads a mailing list from its standard input.

       setmaillist writes the mailing list in a binary format to tmp; it then moves tmp to bin.  tmp and bin must be on the same filesystem.

       If there is a problem creating tmp, setmaillist complains and leaves bin alone.

       The binary mailing list format is portable across machines.

       setmaillist always creates bin world-readable.

MAILING LIST FORMAT

       The mailing list read by setmaillist is a series of lines.  NUL bytes are not allowed.

       If a line begins with a dot or slash, setmaillist takes the entire line as an include file name.

       If  a line begins with an ampersand, setmaillist takes the rest of the line as a recipient address.  If a line begins with a letter or num-
       ber, setmaillist takes the entire line as a recipient address.  Each recipient address must include a fully qualified domain name.  Recipi-
       ent addresses longer than 800 bytes are not allowed.

       setmaillist ignores blank lines and lines beginning with #.  It also ignores spaces and tabs at the ends of lines.

       For example,

	  god@heaven.af.mil
	  djb@silverton.berkeley.edu

       is a mailing list with two addresses.

SEE ALSO

       setforward(1), newinclude(1), printmaillist(1)

																    setmaillist(1)
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